We can't find "domain.com"

For some reason a website is not coming up when you type the url in the address bar. The domain is the master domain and is responsible for dns on the server. All other domains work on the server except for this domain, there is 96 domains total and only 95 are working. In addition, httpd.conf looks like nothing is wrong. Also, the IP is pingable. I did dns tests and nothing is wrong with them either. Any ideas of what could be wrong?